Description

The ZLED7720 continuous-mode inductive step-down converter family is designed for applications requiring high brightness and high current. The ZLED7720 can efficiently drive a single LED or multiple series-connected LED's from a voltage input higher than the LED forward voltage: Vin = 6 to 40 VDC. It provides an adjustable output current of less than 1.0A, which is set via an external resistor and controlled by the ZLED7520's integrated high-side output current-sensing circuit and high speed internal 40V power switch. An external control signal, which can be a DC voltage, PWM, or microcontroller-generated waveform, on the ADJ pin can also be used to linearly adjust a continuous output current or to control a gated output current.

The output can be turned off by applying a voltage lower than 0.2V to the ADJ pin, which puts the ZLED7720 in a low-current standby state. The ZLED7720 enables diverse industrial and consumer lighting applications requiring high driving currents, wide operating voltage range, high efficiency, and variable brightness control. It offers over-temperature and LED open-circuit protection. The ZLED7720 can also minimize bill-of-material costs because very few external components are required for most applications.

Only a resistor, a diode, an inductor, and a capacitor are needed for a typical basic application. For easy evaluation of the ZLED7720, an evaluation kit is available.

Features

• Up to 0.35A output current
• Internal 40V power switch
• Wide DC input voltage range 6 to 40 VDC
• Output current accuracy: 3% (typical)
• Dimming ratio: 1200:1
• LED open-circuit protection
• Thermal shutdown protection

Benefits

• High efficiency: up to 98%
• Single pin on/off and brightness control using DC voltage or PWM
• Very few external components needed for operation
• Footprint compatible to ZLED7000

Typical Uses

• MR16/MR11 LED spot lights
• LED street lights
• Parabolic aluminized reflector (PAR)
• LED lights
• Other general purpose industrial and consumer LED applications